The primary goals of this project are to advance understanding of 1) the long-term cardiovascular disease (CVD) prevention potential of a multifactor intervention program aimed at cigarette smoking cessation and the lowering of blood cholesterol and blood pressure and 2) the relationships of these and other risk factors to cardiovascular and cancer mortality data through calendar year 1991 (proving 16.5 years of followup) and analyses of the extensive data set collected during the Multiple Risk Factor Intervention Trial (MRFIT) and subsequent long-term mortality followup. From the screening of over 360,000 men, the MRFIT investigators recruited 12,866 men age 35-57 at above average risk of death from coronary heart disease (CHD). These men were randomized to a special intervention (SI) or to a usual care (UC) group. At the conclusion of the trial in 1982, the SI men compared to UC men had a 7.1% lower CHD death rate, a 4.7% lower CVD death rate, and a 2.1% higher death rate from all causes. None of these differences were statistically significant. Since 1982, numerous scientific reports have been published based on data collected during the trial. Recently, data have become available to bring the average duration of mortality followup to 10.5 years. At the time of this extended followup, the SI men compared to UC men had a 10.2% lower CHD death rate (a 24.3% lower rate for acute MI), and 8.3% lower CVD death rate and a 7.7% lower death rate from all causes. With the exception of the significant difference for acute MI., these differences approach but do not attain statistical significance. It is proposed to examine intervention efficacy and the relationships of the various risk factors to mortality form CVD (including stroke) and major sites of cancers analyses based on 16 year followup data that could not be done previously because of small numbers of deaths for some causes of death and for some subgroups of the population. Data collected during the MRFIT on smoking habits, blood pressure, lipids, diet, drug treatment, electrocardiography and other risk factors are among the most detailed and carefully controlled for quality among large epidemiologic studies.